Descaling depends the size of the reservoir. I see the B60 but not the B66 at the Keurig site. The two units are apparently the same from searching the support side of the Keurig site: http://www.keurig.com
For the Mini coffee makers, you use 20 oz of vinegar (2 10 oz cycles). For the larger Keurig units, it takes 48 oz of vinegar.
In either case, fill the reservoir with vinegar and put a large ceramic (12 oz mug for the mini unit) mug on the drip tray. Do not add a K-cup. For the B60 (and probably the B66), press the Brew button. Discard the vinegar after the cycle. Repeat the brew process until Add Water is indicated. Discard the vinegar each time. Then wait 4 hours with the unit on. Discard the remaining vinegar and rinse the reservoir. Fill the reservoir with 48 oz of water and brew several cups without a K-cup until the "Add water" message appears. Discard the water in the mug each time. Repeat the vinegar cleaning if De-scale still appears in the LCD. Run more water without the K-cup if you notice a remaining taste in the coffee after the rinse procedure.
For the mini, fill the reservoir with 10 oz of water, lift the Brewer handle and lower it after 5 seconds with no K-cup in the unit. Press the Brew button. Discard the vinegar after the cycle. After the first cycle, pour the other 10 oz of vinegar into the Cold Water Reservoir. Lift the handle and lower it after 5 seconds. Press the Brew button and wait until the light becomes steady. When vinegar starts to be dispensed, power off the unit. Wait 30 minutes. Then power on the unit and lift and lower the handle again. Then discard the vinegar after the cycle. Next run 4 rinse brew cycles with 10 oz of water each time. Discard the water each time. The unit should be ready to brew with a K-cup after the 4 rinse cycles.
I hope this helps.